1. Technical Field
The inventive concept relates to methods of forming a semiconductor device.
2. Discussion of the Related Art
A static random access memory (SRAM) is a type of semiconductor memory.
Generally, an SRAM cell is made up of two pull-down elements, two access elements, and two pull-up elements. The SRAM cell may be categorized as a full complementary metal-oxide semiconductor (CMOS) cell, a high load resistor (HLR) cell, or a thin film transistor (TFT) cell according to the pull-up elements. The full CMOS cell uses p-channel bulk MOSFETs as the pull-up elements. The HLR cell uses poly-silicon patterns having a high resistance value as the pull-up elements. The TFT cell uses p-channel poly-silicon TFTs as the pull-up elements.